Abstract:This report demonstrates that digital television (DTV) susceptibility to gated-noise interference cannot be predicted by interference power characteristics alone. It was found that DTV susceptibility is also dependent on temporal characteristics of the interfering signal and the bandwidth of the DTV receiver. A test system was developed to inject interference with known characteristics into a victim receiver and quantitatively measure susceptibility. In this experiment, a C-band satellite DTV victim receiver was exposed to gated-noise interference, whose temporal characteristics are defined by gating parameters such as on-time, fractional on-time, and off-time. The specific gating parameters considered in this report include on-times of 0.01, 0.10, 1.00, and 10.00 µ and fractional on-times of 1.00, 0.50, 0.25, 0.125, and 0.0625. Results showed that DTV susceptibility was strictly dependent on average power of the interfering signal only when off-times were less than the reciprocal bandwidth of the victim receiver. For longer off-times, however, susceptibility was dependent on the temporal characteristics of the interfering signal. Moreover, high correlation was observed between susceptibility and forward error correction performance of the receiver.

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